In 1999 the National Public Security Force (Portuguese: Força Nacional de Segurança Pública) was created to handle any significant security crisis. The unit, which is composed of the most qualified Military Police personnel from all federal states, can only be deployed through the express command of a state governor.

In 1834 Pedro I died in Portugal and this reduced the fear in Brazil of a reunification of the kingdoms. The Guard of Volunteers were then transformed into Province Police Corps, with professional troops.[8] The Police Corps were created with the same structure as the Army, and to serve as reserve troops when necessary.

With the Proclamation of the Republic, Brazil adopted a constitution based on the United States' one, where the states have a large autonomy. The Corps of Police began to be administered by the states and became smaller regional armies, with infantry, cavalry, artillery, and later, even with air forces. This dangerous situation to the national security remained until the end of World War II, with the deposition of the dictatorial government of Getúlio Vargas.

After World War II, the Military Police assumed the roles of a more "traditional" police force, similar to a gendarmerie subject to the states.[9] They sought a rapprochement with the civil society, slowly developing the configuration it currently possesses.

The Secretariat for Public Security (Secretaria de Segurança Pública—SSP) supervises all state police activities. The SSPs are subordinate to the National Council of Public Security (Conselho Nacional de Segurança Pública - CONASP).[10]

According to Article 144 of the federal constitution, the function of the Military Polices "is to serve as a conspicuous police force and to preserve public order." The Military Police of any state are organized as a military force and have a military-based rank structure. Training is weighted more heavily toward police matters, but counterinsurgency training is also included. Arms and equipment of state forces include machine guns and armored cars, in addition to other items generally associated with police.[10]

Article 144 of the constitution stipulates that: "The Military Police forces and the Military Firefighters Corps, ancillary forces and army reserve, are subordinate, along with the Civil Police forces, to the governors of the states, Federal District, and territories." Between 1969 and 1985, the Ministry of Army has controlled the Military Police during periods of declared national emergency. Before 1930 these forces were under individual state control, and known as "the governors' armies." They sometimes outnumbered regular troops in many states. In 1932, after Constitutionalist Revolution in São Paulo, the Federal Army took steps to reverse this situation. In 1964 most Military Police members were on the side of the successful conspirators.[10]

During military dictatorship, Military Police units were often commanded by active-duty army officers, but that has occurred less frequently as professional police officers have achieved higher ranks and positions. The commandant of a state's Military Police is usually a Colonel. The command is divided into police regions, which deploy police battalions and companies. Firefighting is also a Military Police function in some states, but they are organized in separate units. State traffic police are either the State Highway Police (Polícia Rodoviária Estadual), or the Traffic Police (Polícia de Trânsito) in the larger cities. Both are part of the state Military Police.[10]

Throughout Brazil the Military Police is known by the acronymPM (for Policia Militar), followed by the abbreviation of the State. Except in the State of Rio Grande do Sul, where the unit is known as BM, (for Brigada Militar, "Military Brigade").

The Brazilian Armed Forces inherited Portuguese military traditions and during the period of the Empire and part of the Republic, with few exceptions, dark blue uniforms were used. In 1903 the Brazilian Army opted for khaki colored field uniforms, later copied by the Military Police. In 1934 the Ministry of War established the color khaki for all the reserve forces.

After the Second World War, the Military Police had the autonomy to adopt its own uniforms, but most stayed with the khaki. During the Military Government in 1976, the Army suggested that the Military Police adopt the blue color (color of the uniform of the Military Police of the Federal District). Since then, some units have changed their uniforms, others have not.

Currently the color khaki (with variations to beige) and blue (with variations of gray to dark blue) prevail in the colors of the uniforms of the Military Police.

The establishment of principles, guidelines and standards for the effective implementation of control and coordination of the Military Police under Command of the Army, through its Military Area Commands, Regions and other Major Military Command;

The control of the organization and legislation, personnel and equipment of military police, such as: